hey , bea
i ran into similar problems with berzerk, berzerk1 , berzerks , berzerkf , berzerkg
make sure nvram file is deleted before recording , some require default nvram that requires
you to boot-up the game , escape , re-enter the game or recording whATEVER THE CASE MAYBE.
also muting the emulator via windows desktop icon is helpful sometimes
experament with different video modes

NVRAM should always be removed or deleted before recording and playback, or even better, set nvram_directory to NUL (or /dev/null if you don't use Windows).

Since it's been known to be problematic pretty much since it was added, it's quite likely to be something you can't control (ie: an issue with the driver).

You could learn C++ and some computer architecture and try to fix the driver, but somehow I doubt you're about to do that.
There is already a bug report about it from a few years ago. http://mametesters.org/view.php?id=4209

yeah, no idea what's wrong with it to be honest, we've ran it through tools that are meant to detect illegal / uninitialized memory accesses etc. and still nothing. it doesn't even have a real time clock to cause issues, bit of a mystery.